Steaming device and method



Oct. 1, 1968 R. K. STEM ET AL 3,403,452

STEAMING DEVICE AND METHOD Filed July 11, 1966 bmmmmm P/Cl-MPO h. 675M WILL/14M 7? .ooLA/V CHARLES c. STEM United States Patent "ice 3,403,452 STEAMING DEVICE AND METHOD Richard K. Stern, William T. Dolan, and Charles C. Stem,

New Albany, Ind., assignors to Chester B. Stem, Incorporated, New Albany, Ind., a corporation of Indiana Filed July 11, 1966, Ser. No. 564,387 3 Claims. (Cl. 3413.8)

ABSTRACT OF THE DISCLOSURE Means and methods for steaming wood. The means includes an elongated tubular body openable at one end and closed at the other, rails within the tubular body upon which wood may be stacked so that the bottom of the stack of wood is spaced from the bottom of the tubular body and steam piping located near the bottom of the tubular body for heating water within the tubular body below the bottom of the stack of wood and the bottom of the tubular body to cause it to boil and fill the tubular body with steam under pressure.

Description of the prior art The steaming or soaking of small wooden parts to soften them so that they may be curved for use in furniture, boat ribs, etc. is an ancient art. The art of steaming has been expanded to straightening cooked logs or crooked poles, piles or posts cut from the boles of crooked trees.

In many instances, large wooden parts are steamed under pressure or treated with hot liquid preservatives under pressure in cylinders or autoclaves. Much attention has been given to methods of straightening or curving wooden parts after steaming and to the various liquid preservatives. However, the cylinders or autoclaves normally employed are so constructed that live steam is injected directly into the autoclave. The steam cools and condenses, however, and must be continually fed into the autoclave to maintain constant temperature and pressure.

While the prior art autoclaves have worked, improved results have been obtained by providing an autoclave in accord with the present invention which comprises an elongated chamber having a plurality of spaced tracks running along the lower surface thereof for supported Wood to be stacked in the chamber. Pipes disposed under the track are covered with water. After the lumber has been loaded into the autoclave and the doors sealed, steam is circulated through the pipes. The pipes act as a large steam radiator and generate sufiicient heat to cause the water to boil, thus providing a constant source of steam. The steam is confined by the autoclave and has the effect of steaming lumber or wood under pressure.

This has been particularly effective in steaming lumber and flitches and has yielded far superior results in steaming of walnut lumber and the like under pressure.

Therefore, it is a primary object of the present invention to provide improved means and methods for steaming wood parts.

It is a further object of the present invention to provide an autoclave having a constant, internally generated steam supply.

It is a further object of the present invention to pro vide an improved method for steaming wooden parts wherein the steam is not allowed to cool and condense.

Related objects and advantages will become apparent as the description proceeds.

One embodiment of the present invention might include a material steaming apparatus comprising an elongated tubular body having an open end and a closed end. A cap is releasably mounted on the open end of the body for closing and sealing the open end. A portion of 3,403,452 Patented Oct. 1, 1968 the tubular body is filled with water. A heat generating means is immersed in the water for causing the water to boil constantly during the steaming operation. The material to be steamed is stacked within the tubular body on support means which maintain the material to be steamed above the water contained within the tubular body.

The full nature of the invention will be understood from the accompanying drawings and the following description and claims.

In the drawings:

' FIG. 1 is a side elevation of an illustrative embodiment of an autoclave in accord with the present invention;

FIG. 2 is a bottom plan view of the autoclave with dotted lines representing the steam pipes and the supporting tracks; and t FIG. 3 is a section view taken through section 3-3 of FIG. 1.

For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawing and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.

The steaming device 10 of the present invention comprises an elongated tubular body 11 having an open end 12 and a closed end 13. A cap 14 is releasably mounted on the open end 12 of the tubular body 11 for enclosing and sealing the open end during the operation of the steaming device. A portion of the tubular body 11 is filled with water 15. The material to be steamed 16 is supported above the water by support means 17.

A heat generating means is disposed along the longitudinal axis of the tubular body and supported therein. From the drawings it can be seen that the heat generating means includes first and second opposite-1y disposed elongated substantially U-shaped pipes 18 and 19. The configuration of the pipes is shown by the dotted lines in FIG. 2. Pipes 18 and 19 have a closed end 20 and 21, respectively. The closed ends 20 and 21 are adjacent ends 13 and 12, respectively, of the tubular body 11. Pipes 18 and 19 have legs 22 and 23, respectively, which are shorter than legs 24 and 25 of pipes 18 and 19, respectively, so that when leg 22 and leg 23 are coupled, legs 24 and 25 do not meet.

It can be seen from the drawings that the heating apparatus in the representative embodiment is more or less an elongated substantially continuous loop of pipe which allows circulation of steam around the loop. A steam inlet pipe 26 is coupled to and sealed with the free end of leg 24 of pipe 18 at junction 27. Similarly a steam outlet pipe 28 is coupled to and sealed to the free end of leg 25 of pipe 19 to provide a steam outlet. Both the steam inlet pipe 26 and the steam outlet pipe 28 extend from the tubular body 18. The free ends of pipes 26 and 28 are connected to a conventional steam generating and circulating source, which arrangement does not include the present invention.

The circulating steam heats the water 15 within the steaming device 10, causing it to boil constantly during the steaming operation. Thus, pressure is built up within the steaming device and a constant pressure and steam atmosphere is maintained throughout the operation.

It can also be seen from the drawings that the heating apparatus is disposed along the longitudinal axis of the tubular body 10 and is centrally located therein. FIG. 3

shows that the pipes 18 and 19 of the heating apparatus are spaced from the bottom wall of the container and completely immersed in the water to provide even heating. The heating apparatus is supported within the tubular body and spaced from the bottom thereof by conventional support means (not shown).

The means for supporting the stack 16 of material to be steamed includes a plurality of spaced apart tracks 17 as shown in FIG. 2. Each of the track means 17 is disposed along a transverse plane of the tubular body 11. The track means are supported above the water by a pair of brackets 30 and 31 which are disposed on either side of the heating element or on either side of pipes 18 and 19 respectively. Each of the track means 17 is coupled to its respective brackets by a coupling member 32.

The outer dotted lines in FIG. 2 indicate the position of the lumber within the tubular body with respect to the track or supporting members 17.

It is to be understood that the drawings and the above description represent one embodiment of the present invention. The main feature of the invention is that water is contained within the steaming device and a heating element is immersed within the water which constantly maintains the water at its boiling point during the steaming operation. The support means only requires that there be spaces or openings through which the steam can rise to reach the wood or other material that is stacked therein. This apparatus and method of stacking wood within a steaming device wherein the steam is generated from within the device itself rather than introduced from an external source has been particularly successful in the steaming of walnut veneer.

While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, is being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention and the scope of the claims are also desired to be protected.

The invention claimed is:

1. A material steaming apparatus comprising: an elongated tubular body having an open end and a closed end; means releasably mounted on said open end of said tubular body for enclosing and sealing said open end; a portion of said tubular body filled with water; means for supporting a stack of material in said tubular body for steaming purposes, said supporting means positioned above said water contained within said tubular body;

heat generating means disposed along the longitudinal axis of said tubular body and immersed in said water for causing said water to boil and generate steam within said tubular body; means for supporting said heat generating means above the bottom wall of said tubular body; said heat generating means including first and second oppositely disposed elongated substantially U-shaped pipes, each of said pipe members having a closed end, a first leg and a second leg, said second leg being shorter than said first leg so that when said first leg of said first pipe is coupled to said first leg of said second pipe, the end of the second leg of said first pipe and the end of the second leg of said second pipe are free; said apparatus additionally comprising inlet means for introducing steam into said free end of said first pipe, said steam "traveling through said first pipe and said second pipe,

and outlet means for egress of steam from said second pipe.

2. A material steaming apparatus in accord with claim 1 wherein said means for supporting said stack of material includes a plurality of spaced apart track means, each of said track means disposed along a transverse plane of said tubular body, each of said track means supported above said water by a first bracket means, said bracket means coupled to said inner bottom wall on one side of said heat generating means and a second bracket means coupled to said inner bottom wall on the other side of said heat generating means, means for coupling each of said track means to its respective first and second bracket means.

3. In a method for steaming wood the steps of: (a) stacking said wood on support means within an autoclave means, said autoclave means containing water in the bottom of said autoclave means, said support means maintaining said wood above said water; (b) sealing said autoclave means; and (c) heating said water within said autoclave means so that said water boils constantly during the steaming operation.

References Cited UNITED STATES PATENTS 1,328,505 1/1920 Fish 3413.8 X 1,760,444 5/1930 Secord 34-9.5 X 2,422,557 6/1947 Kobiolke 349.5

JOHN J. CAMBY, Acting Primary Examiner. 

